1. Field of the Invention
The invention relates in general to an optical touch module and a touch display using the same, and more particularly to an optical touch module, which projects and transmits a light to a transparent substrate and realizes optical touch control according to whether the light is totally reflected, and a touch display using the same.
2. Description of the Related Art
With the rapid advance in science and technology, touch display has been widely used in various electronic products. The touch display may be categorized into for example, resistive touch panel, capacitive touch panel and optical touch panel. Let the optical touch panel be taken for example. The optical touch panel normally has a light source and an image sensor. When the user triggers a touch event within the touch area, an object which touches a touch point blocks the light such that the image sensor senses a dark point corresponding to the position of the touch point in a sensed image. Based on the position of the dark point in the sensed image, the angle of the line connecting the touch point and the image sensor with respect to the edge of the touch panel may be obtained through calculation. As the distance between the touch point and the image sensor is known, the coordinates of the touch point with respect to the display panel may be obtained by the triangulation location method.
For the image sensor to be able to sense an image within a touch area, the positions of the light source and the image sensor in a conventional optical touch module are higher than the touch surface of the touch panel, so the touch panel cannot be realized as a full-flat touch panel. Therefore, how to provide a full-flat optical touch module has become an imminent task for the industries.